Device to prepare and administer two-component mixture

ABSTRACT

A device to prepare and administer a two-component mixture, including a first chamber in which a container is housed that is hermetically closed for a liquid component, a second chamber containing a powdered component, an opening of the container of the liquid component, a mixing member placed in the second chamber for preparing the mixture and a piston able to move in the second chamber to dispense the mixture. The mixing member includes a stem, passing through an opening for dispensing the mixture in the second chamber, having an outer end equipped with a handle and an inner end provided with a mixing blade connected to the inner end with a releasable connection.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a division of application Ser. No. 13/122,129 filed Mar. 31,2011 which is a U.S. National Stage of International Application No.PCT/M2010/050320 filed on Jan. 25, 2010, the entirety of which isincorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention concerns a device to prepare and administer atwo-component mixture.

More specifically, the present invention concerns a device for preparingand administering a bone cement consisting of two components, one ofwhich is liquid and the other is powdered.

BACKGROUND

Devices for preparing and administering bone cement are known thatcomprise two separate chambers in which the two components that make upthe bone cement are stored, said components typically being a liquidcomponent and a powdered component. As known, in order to obtain aneffective application of the bone cement during surgery, such twocomponents must be mixed on the spot, i.e. in the operating room whenthe operation is being carried out.

In some known devices the liquid component is enclosed in a hermeticallyclosed container, like for example a glass vial, so as to maintain thesterility of the component itself and to avoid it being lost into theatmosphere, since it is particularly toxic to people in the operatingroom. The aforementioned container is usually housed in one of the twochambers of the device and is opened or broken at the moment of use, sothat the liquid itself then flows, in a spontaneous or forced manner,into the chamber in which the powdered component is stored to mix withit.

The bone cement thus obtained is dispensed through a mobile pistoninside the mixing chamber, through a suitable opening.

In known devices the mixing of the two components, after they have beenbrought into contact with each other in the way described, can takeplace by manual shaking by the operator, or else by using a specialmixing member, which acts inside the chamber in which the two componentsare located.

In order to make it easier to mix the two components, in some knowndevices the mixing member is positioned coaxial to the dispensing pistonand on the opposite side with respect to it: this arrangement of thecomponents allows the device to be held securely and comfortably duringthe actuation of the mixing member.

At the same time, such an arrangement of components, for reasons ofpracticality, simplicity and cost-effectiveness of production, requiresthe dispensing of the mixture to occur from the same opening throughwhich the mixing member passes and is actuated.

In some known devices, at the end of the device with which the mixingmember is associated, there is a cap to which the member itself isconnected. At the end of the preparation of the mixture, it is necessaryto remove the cap together with the mixing member in order to be able todispense the preparation thrusted by the piston. This last operation, aswell as being cumbersome and not very practical during surgery in anoperating room, is not without drawbacks.

Firstly, indeed, there is a high probability of the preparation, whenexposed to the air, contaminating, becoming unsuitable for application.

Secondly, it can accidentally come out from the device placing thehealth of the people present in the room at risk due to its hightoxicity, and requiring a series of other provisions and safety measuresto protect these people.

SUMMARY OF THE INVENTION

The technical task of the present invention is therefore to improve thestate of the art.

In such a technical task, a purpose of the present invention is toprovide a device for preparing and administering a mixture of twocomponents that is practical and safe to use both during the preparationof the mixture and when the preparation is being dispensed.

Yet another purpose of the present invention is to provide a device forpreparing and administering a mixture of two components without risk ofcontamination and/or leaking of the mixture while it is being dispensed.

A further purpose of the present invention is to make a device toprepare and administer a two-component mixture that allows theapplication of the mixture to be simplified and made morecost-effective, mainly but not exclusively in terms of the measures forprotecting personnel.

These and other purposes are all accomplished by the device to prepareand administer a two-component mixture according to one or more of theattached claims.

An important advantage achieved by the device according to the presentinvention consists of the fact that the dispensing of the mixture takesplace without risk of contamination of the preparation by contact withthe outside.

Another advantage achieved by the device according to the presentinvention consists of the fact that the risks of dispersion of theprepared mixture into the outside environment are eliminated.

Yet another advantage achieved by the device according to the presentinvention consists of the fact that, once the preparation of the mixturehas ended, the dispensing thereof during surgery can be performed with aquick and simple manual operation, which does not require furtherequipment or particularly complex safety measures.

A further advantage achieved by the device according to the presentinvention consists of the fact that the preparation of the mixture ofthe liquid component and of the solid component can be carried out in apractical and safe manner that is comfortable for the operator.

BRIEF DESCRIPTION OF THE DRAWINGS

These and further advantages will be more clearly understood by any manskilled in the art from the following description and from the attacheddrawings, given as non-limiting examples, in which:

FIG. 1 is a perspective view of the device according to the invention;

FIG. 2 is a further perspective view of the device according to theinvention;

FIG. 3 is a side view of the device;

FIG. 4 is a section view of the device;

FIG. 5 is a section view of the device in an initial step of thepreparation of the mixture;

FIG. 6 is a section view of the device in a subsequent step of thepreparation of the mixture;

FIG. 7 is a section view of the device in another step of thepreparation of the mixture;

FIG. 8 is a section view of the device in yet another step of thepreparation of the mixture;

FIG. 9 is a detailed section view of the device in a final step of thepreparation of the mixture;

FIG. 10 is a detailed section view of another embodiment of the device;

FIG. 11 is a detailed section view of yet another embodiment of thedevice;

FIG. 11A is a detail of FIG. 11;

FIG. 12 is a detailed section view of yet another embodiment of thedevice; and

FIG. 13 is a detailed section view of a further embodiment of the deviceaccording to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the representation of FIG. 1, a device for preparingand administering a mixture of two components according to the inventionis wholly indicated with 1.

The device is particularly, but not exclusively, recommended forpreparing a mixture consisting of bone cement, deriving from the unionof a liquid component and a solid component, to be administered to thepatient in certain types of surgery, for example osteoplastic surgery orsimilar. In order to obtain a suitable product, such preparation takesplace, as known, in an operating room while the surgery itself is beingperformed.

The device 1 comprises a tubular body, wholly indicated with 2, with asubstantially cylindrical configuration; at one of the bases the tubularbody 2 is open, and defines a circular mouth 3.

The tubular body 2, at the mouth 3 and at the mid-way point, has twocollars 4 that are joined and ergonomically configured that allow it tobe held more easily during the preparation of the mixture; moreover, thetubular body 2 is equipped with an outer ring that can be used both tomake it easier to hold and to connect or fix the device onto othermachines or equipment.

The tubular body 2 can, for example, be made from plastic material, orelse from any other material—for example metal or glass—that is suitablefor containing the two components that will constitute the mixture.

The mouth 3 of the tubular body 2 has a piston 6 engaged in it, whichhas the function of dispensing the prepared mixture, as will becomeclearer hereafter.

The piston 6 is engaged in the mouth 3 so as to be able to slideaxially; the piston 6 is equipped with a head 7 carrying a first sealinggasket 8 along the inner surface of the tubular body 2. Alternatively,the piston can be coupled with the tubular body 2 through a screw-nutscrew connection, allowing the operator to act with greater easeconsidering the high density and viscosity of the mixture produced. Atthe opposite end with respect to the head 7, the piston 6 is providedwith a substantially discoidal handle 9 that allows it to be actuated,as described hereafter.

As can be seen, for example, in FIG. 4 and thereafter, the piston 6 ismade internally hollow: the cavity of the piston 6 constitutes a firstchamber 10 for the liquid component 11 that will constitute the mixture.

The tubular body 2, on the other hand, defines a second chamber 12inside it, in which the powdered component 13 that has to be combinedwith the liquid component 11 coming from the first chamber 10 iscontained. The second chamber 12 is closed by the head 7 of the piston6.

In the tubular body 2 there is also an opening 14 for dispensing themixture, indicated with 15 in FIG. 7 and thereafter; such a dispensingopening 14 is suitable for placing the second chamber 12 selectively incommunication with the outside, and is opposite the mouth 3 in which thepiston 6 is inserted.

The first chamber 10 and the second chamber 12 of the device communicatewith each other through small substantially axial holes 16 foreseen inthe head 7 of the piston 6.

The liquid component 11, which is volatile and toxic if released intothe atmosphere, is enclosed in a hermetically closed container 17: sucha container 17 consists, for example, of a glass vial. The container 17can, nevertheless, be of another shape or another material, suitable forsafely enclosing said liquid component 11. The container 17 is housed inthe first chamber 10 defined in the piston 6, as can be seen in FIG. 4.

The device also comprises means for opening the container 17 of theliquid component 11, wholly indicated with 18. Such means 18 for openingthe container 17 comprise a fracturing member 19, associated with thehandle 9 for actuating the piston 6, selectively mobile from an outerposition—represented in FIG. 5—to an inner position—represented in FIG.6—pressing on a first end of the container 17, to cause it to break. Ingreater detail, the fracturing member 19 is suitable for acting upon thehead of the glass vial 17. The fracturing member 19 consists of a hollowtubular portion equipped with a widening 20 at its outer end, on whichit is possible to press manually; the fracturing member 19 is engaged soas to be able to slide in a bushing 21 that closes a gap 22 for accessto the first chamber 10, made in the handle 9 of the piston 6, withinterposition of a second sealing gasket 23.

The means 18 for opening the container 17 also comprise a protrusion 24,opposite the fracturing member 19 inside the first chamber 10, on whichthe second end of the container 17, i.e. the base of the glass vial,abuts. The protrusion 24 is fixedly connected to the inner face of thehead 7 of the piston 6.

The first chamber 10, foreseen inside the piston 6, is equipped with afilter 25 for holding back the fragments of the container 17 after ithas been broken. Indeed, such fragments, especially the smallest ones,could pass through the holes 16 and mix together, inside the secondchamber 12, with the liquid component and with the powdered component.The filter 25 is positioned at the inner face of the head 7 of thepiston 6, adjacent to the protrusion 24.

The device 1 comprises a mixing member 26, associated with the secondchamber 12, suitable for the preparation of the mixture, i.e. suitablefor making it quicker and easier to mix the liquid component and thepowdered component.

More specifically, the aforementioned mixing member 26 comprisesactuation means 27, for example a through stem able to slide through thedispensing opening 14, suitable for forming the mixture foreseen in thesecond chamber 12.

The actuation means 27 have an outer end 28 equipped with a handle 29for manual actuation, and an inner end 30 provided with the mixingmember 26, for example a mixing blade 31, which carries out the mixingof the liquid component with the powdered component.

The mixing member 26, for example the mixing blade 31, is associatedwith the inner end of the actuation means, for example the stem 27,through releasable connection means 32 that allow the actuation means tobe separated from the mixing member 26.

This provision, as will become clearer hereafter, allows the actuationmeans of the mixing member 26 to be removed at the end of thepreparation of the mixture, thus freeing the dispensing opening 14.

According to another version of the present invention, the releasableconnection means 32 comprise a threaded portion 33 foreseen in the innerend 30 of the stem 27, and a nut screw 34 foreseen in the mixing blade31.

According to an alternative that is not illustrated, the nut screw islocated on the stem 27 and the threaded portion in the mixing member 26.

Inside the second chamber 12 the device 1 comprises a constrainingelement 35 for the mixing blade 31.

If the separation of the mixing member 26 from the stem 27 takes placeby rotation, the constraining element 35 is made as an anti-rotationelement: for example a shape connection for suitable portions of themixing member 26, a pin, etc.

The constraining element 35 thus allows the stem 27 to be quicklyremoved from the blade 31 at the end of the preparation of the mixture.

According to a version of the present invention, the constrainingelement 35 comprises an axial pin arranged eccentrically with respect tothe dispensing opening 14 of the mixture.

On the mixing member 26, or on the blade 31, near to the dispensingopening 14, there is also a recess 36 (FIG. 6), or else a hole, etc., inwhich a corresponding portion of the blade 31 is intended to engage atthe end of the preparation of the mixture, so as to make theconstraining element 35 engage in the blade 31 itself.

According to another version of the present invention, the recess 36 isprism-shaped and the blade 31 has a portion with a corresponding shape,and in this case the pin is not present, because the necessaryanti-rotation constraining function is already achieved in this way.

The tubular body 2, at the dispensing opening 14 of the mixture,comprises an appendix 37 for coupling with a further recipient forcollecting the dispensed mixture, not represented in the Figures but ofthe type essentially known. The appendix 37 can be made in a separatepiece from the tubular body 2, mounted with interposition of a thirdsealing gasket 38. Such a coupling appendix 37 comprises screwconnection means to the recipient, wholly indicated with 39; theaforementioned screw connection means 39 can be of the type known in thefield by the trade name “Luer-Lock™”, or other equivalent means.

It should be noted that screw connection means 39 of this type areparticularly recommended since, given the high density and viscosity ofthe prepared mixture, it is necessary to achieve secure and effectivelocking of the recipient, which with other less secure connection meanscould detach precisely due to the pressure of the mixture, compressed bythe piston 6.

In practical use, the device ready for use is in a condition like theone represented in FIG. 5. The preparation of the mixture for subsequentadministration begins by breaking the container 17 of the liquidcomponent 11, as can be seen in FIG. 6. In order to break the container17, the operator presses manually, preferably with a fast and sharpgesture, on the widening 20 of the fracturing member 19. Such pressing,combined with the opposite abutment of the container on the protrusion24, causes the container 17 itself to shatter.

At this point the liquid component 11 is freed inside the first chamber10; through manual traction towards the outside of the piston 6 by theoperator, a depression is created inside the second chamber 12. Then theliquid component 11 is drawn by the depression and transferred into thesecond chamber itself 12 through the holes 16.

It is now possible to mix the two components to obtain the product to beadministered. The operator therefore acts upon the mixing member 26performing a quick alternative rotary and translation movement of themember 26 itself inside the second chamber 12.

After having obtained optimal mixing of the two components 11, 13, theoperator removes the stem 27 of the mixing member 26. In particular, theoperator pulls the mixing member 26 outwards until the blade 31 isengaged in the recess 36, and therefore in the anti-rotationconstraining element 35. At this point, the operator can completelyunscrew the stem 27 from the blade 31, removing it and thus freeing thedispensing opening 14. Advantageously, the operator can now connect theappendix 37 to a recipient for collecting the dispensed mixture, whichwill then be used in the surgical intervention once filled by actingmanually on the handle 9 of the piston 6.

With this solution, important technical advantages are evidentlyobtained.

A first important technical advantage consists of the fact that, oncethe step of preparing the mixture inside the second chamber 12 has endedduring surgery, the operator can proceed, immediately and with simplegestures, to dispense the aforementioned mixture for example inside acollection recipient.

A further technical advantage consists of the fact that the risks ofcontamination of the prepared mixture and also the risks of dispersionof the mixture itself in the environment are substantially reduced.

Yet another technical advantage consists of the fact that the step ofpreparing the mixture is particularly quick and easy thanks to thepositioning of the mixing member 26 at the dispensing opening 14, alsoconsidering the high density and viscosity of the mixture itself thatgenerate substantial resistance to the movement of the mixing member 26.

Yet another technical advantage achieved by the device according to theinvention consists of the fact that the two liquid and powderedcomponents 11, 13 are kept in areas hermetically separated from oneanother and with respect to the outside until the moment of actualpreparation of the mixture.

Another embodiment of the device according to the invention isrepresented in FIG. 10. In this embodiment, the releasable connectionmeans 32 comprise a bayonet coupling. For example, the inner end 30 ofthe stem 27 comprises one or more grooves 40, whereas the bladecomprises one or more ridges 41 suitable for engaging in the groove 40.This embodiment allows the stem 27 to be released from the blade 31 morequickly; however, this solution is recommended for devices suitable forpreparing small amounts of mixture, since the bayonet coupling makes aless solid coupling with respect to one with screw means.

Another embodiment of the device according to the invention isrepresented in FIGS. 11, 11 a. In this embodiment the releasableconnection means 32 comprise a traction breaking portion 42 of the stem27. For example, such a breaking portion 42 can consist of a sort ofthin membrane configured like the inner face of the blade 31, whichfractures perimetrically by traction of the stem 27 and that frees thedispensing opening 14, as can be seen in FIG. 11 a.

Also in this embodiment the removal of the stem can take place extremelyquickly.

Another embodiment of the device according to the invention isrepresented in FIG. 12. In this embodiment, the stem 27 is madeinternally hollow and the releasable connection means 32 comprise abreaking portion 42 foreseen along the side surface of the stem 27itself. By manual traction, the latter fractures into two pieces theinner one of which stays fixedly connected to the blade 31, andtherefore constitutes a channel for dispensing the mixture.

Another embodiment of the device according to the invention isrepresented in 10 FIG. 13. In this embodiment the coupling appendix 37comprises bayonet coupling means 43 with the recipient for collectingthe dispensed mixture. In particular, the appendix 37 comprises at leastone ridge 44 suitable for engaging in a respective groove foreseen inthe mouth of the recipient, not represented in. the Figure but of theconventional type. This solution makes it 15 possible to make theconnection of the device to the collection recipient even quicker andsimpler.

If the device is relatively large in size, to thus produce relativelylarge amounts of mixture, the dispensing opening 14 must also be larger.In this case, so as to still keep the diameter of the stem 27 small, itis possible to foresee a reducer bushing, or other equivalent means, tobe removed together with the stem itself 27.

It has thus been seen how the invention achieves the proposed purposes.The present invention has been described according to preferredembodiments, but equivalent variants can be conceived without departingfrom the scope of protection offered by the following claims.

What is claimed is:
 1. A method for preparing and administering atwo-component mixture, actuated with a device, wherein the methodcomprises the following steps: breaking a container of a liquidcomponent; transferring the liquid component from a first chamber to asecond chamber; mixing the liquid component and a powdered componentthrough a mixing member, making a mixture; removing a stem of saidmixing member; and acting upon a piston to dispense said mixture.
 2. Themethod of claim 1, wherein the container is housed in the first chamberthat is hermetically closed for the liquid component.
 3. The method ofclaim 1, wherein the second chamber contains the powdered component andcommunicates with said first chamber.
 4. The method of claim 1, furthercomprising means for opening said container of the liquid component andwherein the mixing member is associated with said second chamber forpreparing the mixture.
 5. The method of claim 1, wherein the piston isable to move in said second chamber to dispense the mixture.
 6. Themethod of claim 1, wherein said mixing member comprises means foractuating the mixing member itself, said actuation means being able tobe actuated from outside of the device, said actuation means and saidmixing member being associated through releasable connection means. 7.The method according to claim 1, wherein said step of transferring theliquid component from said first chamber to said second chamber iscarried out through traction towards the outside of said piston.
 8. Themethod according to claim 1, wherein said step of mixing the liquidcomponent and the powdered component is carried out through alternativerotary and translation movements of said mixing member inside saidsecond chamber.
 9. The method according to claim 1, wherein said step ofbreaking said container is carried out by pressing manually on saidfracturing member.
 10. The method according to claim 1, furthercomprising a step of connecting a recipient for collecting the dispensedmixture to said device.
 11. A method for preparing and administering atwo-component mixture, actuated with a device, wherein the methodcomprises the following steps: breaking a container of a liquidcomponent; transferring the liquid component from a first chamber to asecond chamber; mixing the liquid component and a powdered componentthrough a mixing member, making a mixture; removing a stem of saidmixing member; and acting upon a piston to dispense said mixture fromthe same opening through which the mixing member passes and is actuated.12. The method of claim 12, wherein the container is housed in the firstchamber that is hermetically closed for the liquid component.
 13. Themethod of claim 12, wherein the second chamber contains the powderedcomponent and communicates with said first chamber.
 14. The method ofclaim 12, further comprising means for opening said container of theliquid component and wherein the mixing member is associated with saidsecond chamber for preparing the mixture.
 15. A method for preparing andadministering a two-component mixture, actuated with a device, whereinthe method comprises the following steps: breaking a container of aliquid component; transferring the liquid component from a first chamberto a second chamber; mixing the liquid component and a powderedcomponent through a mixing member, making a mixture; wherein said mixingmember comprises means for actuating the mixing member itself, saidactuation means being able to be actuated from outside of the device,said actuation means and said mixing member being associated throughreleasable connection means; removing a stem of said mixing member; andacting upon a piston to dispense said mixture.
 16. The method of claim16, wherein the container is housed in the first chamber that ishermetically closed for the liquid component.
 17. The method of claim16, wherein the second chamber contains the powdered component andcommunicates with said first chamber.
 18. The method of claim 16,further comprising means for opening said container of the liquidcomponent and wherein the mixing member is associated with said secondchamber for preparing the mixture.
 19. The method of claim 16, whereinthe piston is able to move in said second chamber to dispense themixture.